This invention relates generally to x-ray tube anode targets and, more particularly to rotating anode targets with high heat dissipation.
As stated in U.S Pat. No. 4,132,916 which is commonly assigned and the teachings of which are incorporated by reference, it is well known that of the total energy involved in an electron beam striking an x-ray target, only 1% of the energy is converted into x-ray radiation with the remainder of about 99% being converted into heat. The power flux under the electron beam on the x-ray target is extremely high making rotation of the target at 10,000 rpm necessary to avoid melting the tungsten on the focal track used to generate the x-rays. In view of this high generation of heat, it is necessary to dissipate the heat from the focal track so as not to destroy the anode target. This heat dissipation to be effective should disperse the heat energy under the beam on the target as well as to transfer the heat out of the target area. This is effected in conjunction with circulating oil in a casing as described in U.S. Pat. No. 4,132,916.
Most x-ray tubes rely on fast rotation of the target to spread the energy in the beam out over the entire target. The thermal conductivity of the tungsten in the focal track aids in conducting heat away from the electron beam impact point.
In U.S. Pat. No. 4,392,238, pyrolytic graphite layers are employed to dissipate heat from a focal track in a rotary anode for an x-ray tube. However, there is a need to improve the heat dissipation of an x-ray tube target.
It is, therefore, an object of the present invention to provide an improved x-ray target with higher heat dissipation than those readily available.
Another object of the present invention is to provide a layer of diamond under the target focal track so as to dissipate the energy under the electron beam and over the target.
Still another object is to provide a method for producing in situ a diamond layer on an x-ray tube anode.
These objects and other features and advantages will become more readily apparent upon reference to the following description when taken in conjunction with the appended drawings.